Approximately 7,000 tin miners at high risk for lung cancer will have sputum specimens collected and stored annually for six years. Other biological specimens (blood, urine, and toenails) will be collected and stored during the second year of the study. Followup will be conducted annually during the study to identify all newly diagnosed cancers. Prediagnostic sputum and other biologic samples will be analyzed for potential early markers utilizing a nested case-control approach. Study participants will be taken from those participating in the annual lung cancer screening examinations conducted by the Labor Protection Institute of the Yunnan Tin Corporation (YTC). Inclusion criteria include: current or retired workers between the ages of 40 and 74; a history of 10 or more years of underground mining and/or smelter experience; no proven, active malignancy or serious illness that would interfere with sputum specimen collection; and consent. The purpose of this solicitation is to obtain contractor support that would allow access to the large population of tin miner's at extraordinary risk for lung cancer in combination with the ongoing lung cancer screening program among these high risk YTC tin miners. The contract affords a unique opportunity to collect and test biological specimens, particularly sputum but in addition blood and urine, for the validation and refinement of early markers of lung cancer. The contract also provides a unique opportunity to prospectively examine, by administering questionnaires, a number of potential risk factors such as radon, arsenic, tobacco, diet, biochemical markers of nutrition status, and other potential risk factors in relation to lung cancer incidence.